Study On The Structure Feature,fine Reservoir Prediction And Hydrocarbon Accumulation Rule Of Heidimiao Oil Layer In T Area

With the deepening of the development of Heidimiao oil layer in T area,it is gradually exposed that the distribution of oil and water is complex,and the development scale of sand body changes greatly.This area belongs to fluvial delta sedimentary system,the sand body develops narrow,the lateral change is big.The main sand body in the block has low drilling rate.In the past,well logging data have been used to predict the structure and sand body.Due to the lack of lateral sand body prediction data,which is difficult to meet the need of development adjustment,according to these characteristics in this paper.1.The theories of tectonic geology,seismology,sedimentology and petroleum geology are comprehensively utilized in this paper,under the premise of regional stratigraphic correlation and the understanding of sedimentary system,Stratigraphic correlation of Heidimiao reservoir in the working area by combining well and earthquake,establishment of sequence development and Seismic Reflectance structural Styles.Using various methods to identify the tracing strata and faults,and to establish the stratigraphic and structural framework,development of seismic attribute analysis and optimal inversion method for prediction of reservoir distribution in Heidimiao reservoir.Analysis of oil-water distribution law,reservoir forming characteristics and main controlling factors.Summing up the model of reservoir formation.Comprehensive evaluation of oil and gas potential in the Heidimiao oil layer.Get the following conclusions:2.The Heidimiao reservoir in T area is a precession quasi-sequence assemblage,which presents an upper thick and lower thin anti-cyclic assemblage sand reservoir,indicating that this set of strata belongs to delta front sedimentation.The types of sedimentary mainly include three types of sand bodies: mouth bar,distal bar and front sheet sand.Through attribute and inversion,it is found that the sandstone of HI reservoir is mainly distributed in the west and southeast of the study area,and the distribution of sandstone is near to north and south.The sandstone of the HII reservoir is developed relatively,and the plane distribution is wide relatively.The thickness of sandstone is generally between 12 and18 m,from north to south,and the main layer is HII5 small layer.3.The vertical distribution of oil and water in the block is more regular.The HI reservoir group is dominated by water and dry layers.The HII reservoir group is composed of pure oil layer,upper underwater oil and pure water layer.The HII reservoir is mainly distributed in the HII5 sublayer.There are 9 layers in the reservoir and the total thickness is about 37.5 m,accounting for 40% of the total sandstone thickness.On the plane,the high part of the monoclinic structure in the west of the study area is the main pure oil layer,which decreases to the east along with the structure,and gradually transition into the oil and water same layer and the water layer.4.The reservoir of Heidimiao Formation is the following reservoir,fault up transport,lithologic occlusion and accumulation mode.Two sets of under compacted high pressure in the lower part of Heidimiao reservoir,which hindered the further upward migration of oil and gas,and accumulated in the mouth bar sand body of HII5 and HII1-2 front edge.5.Two reservoirs,HII5 and HII1-2,have good development potential.The area of favorable area of sandstone above 6 m in the former is 50.4 km2,and that of the latter is 18.9km2.